Application of tunable diode laser spectroscopy to the real-time analysis of engine oil economy

摘要

Abstract: Tunable Diode Laser Spectroscopy (TDLAS) of oil derivedSO$-2$/ in automotive exhaust demonstrated acceptablerepeatability in determination of oil consumption atsteady state engine operating conditions. The responsetime of the instrument was approximately 30 sec, thetime related to the flow rate of the sampling system.Instrument sensitivity is sufficient to measure SO$-2$/levels of 0.1 to 1 ppm required to the oil consumptiondetermination. Typical exhaust gas species wereinvestigated for their interference effects and wereobserved to have less than a 10% interference on theSO$-2$/ signal for mixing ratios with SO$-2$/ typicalof automotive exhaust. Water, on the other hand, didshow a significant, but compensatible interference.Carbon deposition under rich engine conditions wasobserved and is expected to be a problem for anyanalytical device and is best solved by using a heatedsampling line.!